Question: $\dfrac{7}{5} - \dfrac{1}{8} = {?}$
Answer: $ = {\dfrac{7 \times 8}{5 \times 8}} - {\dfrac{1 \times 5}{8 \times 5}} $ $ = {\dfrac{56}{40}} - {\dfrac{5}{40}} $ $ = \dfrac{{56} - {5}}{40} $ $ = \dfrac{51}{40}$